The atmosphere whistles while scientists work. Series of whistles — short or long, going up scale or down — keep radio scientists busy deciphering their messages of the density of charged particles in the outer regions of the earth’s atmosphere.… Generated by lightning as it strikes the earth, the radio waves are propagated back and forth in the atmosphere of the earth, in a north-south direction…. By analyzing the duration of the whistle tone, the length of time it lasts, and the changes as...